Steam-boiler



(N0 Model I) 3 Sheets-Sheet 1.

M. S. POOTE.

STEAM BOILER.

No. 552,754. Patented Jan. '7, 1596.

flz'r/znes s as I nv 674K011 3 Sheets-Sheet 3. M. S. FOOTH,

$TEAM BOILER.

Patented Jan.57 1896.

(No Model) IMGVZZOZ'.

UNITED STATES PATENT QFFICE.

MARK S. FOOTE, OE BURLINGTON, IOXVA.

I TEA -BoIL R.

PECIFICATIO forming part of I etters r atent No. 552,754, dated January7, 1896.

' Application filed lfovember 12, i895. Serial No. 568,709. (No am.)

To wZZ whom it may concern: Be it knownthat I, MARK S. Foorn, ofBur-flington, in the county of Des liloines and State of Iowa, have inventeda new and use- I by a boilerand furnace of simple construction and onethat requires comparatively little attention. I

'The principal results secured by this in-. vention are large area ofheating surface without complicating the construction or multiplyingparts and thorough consumption of the fuel, economizing in coal andreducing the amount of soot and smoke; l

The principal parts of the boiler are sustained by an outer shell,preferably cylin-, drical, from which is suspended interiorly a magazineconstructed and connected with the outer shell in such manner as toformthree horizontal heating-heads. The magazine is double-walled, formingbetween thetwo walls a water-chamber. Between this and the secondwater-chamber is an annular combustionchamber communicating at the topwith a flue formed between the outer shell and the brick inclosure. Theproducts of combustion pass down this flue in contact with the outershell, pass around the bottom of the latter into a similar flue on theother side thereof, and rise through this flue to the chimney. Anair-box is placed in each of these lines, provided with a passagethrough the outer water-chamber, the heated air entering the annularflre-chamber at about the point of final combustion, whereby the smokeis largely consumed and the heating effect increased.

The invention will be fully comprehended from the following detaileddescription, reference being had to the accompanying drawings, wherein-Figure 1 is a central vertical section. Fig. 2 is a similar view on aplane at right angles to Fig. l, and Fig. 3 is a horizontal section online g y.

The outer shell A is preferably cylindrical in form, and with the innershell 13 forms an annular water-chamber a and a steam-dome 1). Themagazine is formed of the two walls 01), between which is a secondwater-chamber c. The magazine is suspended from the shell or casing B bymeans of a ring E, which, as shown, is flanged and riveted to the casingat one end and to the magazine at the other. This ring forms asteam-passage from the inner water-chamber or section a to thesteam-dome b, the water-level in the latter being indicated by the line5c 00. A manhole-cover is provided for access to the interior of theboiler. The inner chamber or boiler-section c is separated from theouter section a by an annular space d, which is a combustionchamber andflue for the passage upward of the products of combustion. This space iscrossed by the fuel chute or hopper H, which leads .to the side of themagazine, and by a pipe I,

which connects the water-chambers aand c.

The heated products of combustion, rising through the annular space orflue d, collect in the chamber 6 between the heating-heads b and c. Thethird heating-head is formed by the top plate cl of the magazine. Allthese parts, as well as the riveted joints of suspending-ring E, areprotected by water, which, as indicated, stands at the level of the line00.

The construction and arrangement of the grate G and the ash-pit presentno peculiarities.

The furnace is inclosed in brickwork K, which at the front and back ofthe furnace is set in close contact with the shell A, but at the sidesis clear of the shell, thus forming two flues L L, each nearly half thecircumference of the boiler. The vertical brick partitions 70, whichseparate these flues, rest upon the cast-iron boxes M, which formcommunications between the two flues. The gaschamber e connects, asshown in Fig. 2, with the upper end of flue L, and the gases spreadthrough the latter in contact with nearly onehalf the surface of shell Aand pass downward. From the bottom of flue L they pass around the lowerpart of shell A through the passages M into the flue L, and passingupward through the latter they heat the other side of shell A, afterwhich they pass to the chimney through outlet N.

In each flue L L is placed a hot-air box P,

having a space around and between it and the brickwork for circulationof the hot gaseous products of combustion, whereby the air, entering thebox at P, is heated and caused to ascend. A pipe 13 extends through thewaterchamber a and delivers the air into the combustion-chamber d at apoint above the lower edge of the magazine, so that combustion at thispoint is aided and greater heat developed. Although air is shownentering the combustion-chamber at two points, the number of air-inletsmay be varied, and other changes may be made in details of constructionwithout departing from the spirit of the invention.

The boiler may be used for hot-water heating as well as forsteam-heating, and its construction is such that while speciallyadvantageous for burning soft coal it may also be used with hard coal.The only surface upon which soot can deposit, and where it will not beburned off? or detached by the action of the flame, is the head 0. Thishead, however, is on the level of the passage c, Fig. 2, between thegas-chamber c and line L. Consequently by forming an opening q throughthe brick work in line with said passage access maybe had to the surfaceof head 0 for cleaning.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. The combination of the outer annular boiler-section forming the shellof the 111 nace; the inner section and magazine suspended from theformer by a ring which also forms a communicating steam passage, therebeing an annular combustion chamber between the two sections, leading toa gas chamber surrounding the suspending ring; a brick inclosure forminga chamber around the shell separated by vertical partitions into twoflues, one of which communicates at the top with said gas chamber andthe other with the chimney; and horizontal passages connecting saidflues at the bottom, substantially as described.

2. The combination of the outer annular boiler-section, the innerannular section and magazine, the suspending ring forming with the wallsof said sections a gas-chamber, and a brick inelosure forming a flueoutside the outer section communicating with said chamber by a passagein line with the level of the top-surface of the inner section, thebrick inclosure being provided with a horizontal opening in line withsaidpassage, substantially as described.

3. The combination of the annular boilersection surrounding the fire-boxand combustion chamber, the inner section suspended therefrom andforming the inner wall of the annular combustion chamber and themagazine, the brick-work forming flues outside the outer section, and ahot air-box in one of said flues, communicating with said combustionchamber at a point above the lower edge of the magazine, substantiallyas described.

4. The combination with the annular boilersection surrounding thefire-box and combustion chamber, and the brick-work, forming flucs onopposite sides of said section, these fiues being connected asspecified, of a hotair boX in each flue around which boxes the productsof combustion circulate, and airducts passing through saidboiler-section to the combustion chamber, substantially as described.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

MARK S. FOOTE.

\Vitnesses A. O. I-IUTcrn-NsoN, F. GonDEcKE.

